Hi, Susan, Quoting Susan Kline <skline@peak.org>: > At 04:06 PM 2/4/2005 -0800, you wrote: > >(Maybe Susan has a copy?) > > Susan JUST HAPPENS to have a copy -- not having a son to "tidy up" my > files, I have been able to go right to it. Of course it helps that this > post dates from 1997, back when I still took the time to sort and > organize. > Back then I thought that if my In Box had 300 posts I was way behind. I > had > yet to discover that Eudora can handle 5000+ posts in a box and (usually) > not tangle or lose any. Sometimes I wish she WOULD lose some ... AHA! Thank you! Avery also had found and sent along a copy. I am presently revising what is included in this one...hopefully to include more information and clarity. I have discovered that Andy left all my stuff very neatly stacked...all in one file drawer, in whatever order they happened to have come to hand...so, at least there is a central location! Best. Horace > > Best, > Susan > > > ************************************************************************** > In November, 1997, Horace wrote (to Avery): > ************************************************************************** > > NY and Hamburg pianos require very different approaches, depending on > the period of manufacture. > > Some background: > > Prior to W.W.II, both factories manufactured instruments that, while > different in certain ways, were virtually identical in others. So much > so that from the earliest period of the re-establishment of > manufacturing in Hamburg, NY was shipping everything from action parts > to completed pianos to London and Berlin, as well as Hamburg. Yes, parts > came this way as well, and not all models were consistently produced in > both plants. > > The destruction of the Hamburg facilities through the firebombing of > Dresden and Hamburg during W.W.II created a real problem. With the end > of the war, NY had its own problems, and insufficient reserves to > rebuild in Germany. Enter Louis Renner, et al. Renner offered to rebuild > the facilities in Hamburg. There was, of course, a catch. The catch was > that Steinway would have to use actions, back actions, hammers, and > other parts from Renner. This began the real divergence between the two > branches of the company. The Renner parts, while generally conforming to > NY specifications, actually were (are) quite different. The reasons do > not matter, the matter just is what it is. The results are the > differences of touch and tone which we have come to expect from the two > factories. > > What then, are these differences? > > Let's start with NY. > > The following general procedure was in use up through, roughly, the > 1987-1988 production period. > > First, the location of the keyframe and cheek blocks was set relative > to the arms of the case of the piano. In the earlier days, the keyframe > and keybed were then drilled for tuning pins used as locators. Then the > back of the keybed was planed dead flat. The keyframe was roughly fit to > this, (the forefinisher could only rough-set this because it was usually > done without the keys or the stack) and then the dags were installed. > The dags were located by gluing a piece of 1/8th inch veneer to the back > of the keyframe (or the front of the dag, if the foreman was not > looking), and then inserting the keyframe into the action bay and > clamping it in place. The dags were then glued in place at intervals > determined by the location of the veneer pieces. After the glue had set, > the fit of the keyframe was checked again. (There is a lot of > misunderstanding about the purpose of the dags. They are NOT there just > for transportation. They serve the crucial function {in the NY pianos} > of providing stability for the back rail of the action. Too tight, and > the action will not shift reliably. Too loose, and the action flops > around and the touch is not stable.) > > When this is done, the keybed is planed concavely front to back along > the axis of the grain (or perpendicular to the keys, if you prefer). It > is planed such that the depth of the convexity is app. 1/16 inch; and > its deepest point is under the center rail of the keyframe. Then 1/8th > to 1/4th inch of the leading side of the top of the keybed is planed > convex by 1/32nd to 1/16th inch, with the high point at the center of > the keybed. The leading 1/8th to 1/4th inch of the leading edge of the > underside of the front rail is then planed to be a mirror image of the > keybed; that is, convex in the opposite direction by 1/32nd to 1/16th > inch. The keyframe is constructed so that only the end stretchers > between the front and back rail are flat. These are then planed so that > they do not touch the keybed, save at the narrow areas described above. > The procedure for locating the cheek blocks has varied over the > years. The most prevalent iteration being to use the location as set > from the arms, and then locate the brass guides relative to the pins in > the keyframe. > > Once that has been done, the keyframe can be inserted and clamped in > place with the cheek blocks, and the forefinisher can work to perfect > the mating of the keyframe and keybed with (hopefully) fine sandpaper. > This whole thing is a part of the overall forefinishing process, > which, in Steinway's case, is a patent process. (Basically, that means > that not only can it not be copied, but they cannot vary from it and > still legally use the descriptive language from the patent documents.) > The purpose of this section of the forefinishing process is to provide > the most solid connection of the action to the balance of the piano > possible, so that the pianist may get the feedback of the vibrations of > the piano through the keys. (This speaks directly to the recent threads > on the forum, re: "singing rims" etc.) The original patent documents > describe this feedback quite dramatically and make interesting reading > anyway... > > This process was used from very early on, right up through the use of > the Pratt-Read keys and keyframes, until 1985, when the switch was made > to Renner action parts and Renner and Kluge keys and keyframes. > Servicing keyframes from this period is usually a process of figuring > out what was done during the original manufacture and why it was done. > Most often, in my experience, this has involved some degree of seeing > through the mist created by some well-meaning, but ill-advised > colleague. Basically, even if some set of arbitrary numbers seem to be > out of whack, if the original work seems to have been done a certain > way, just follow that. There is usually some (good) reason that > something was done, and most of the time, you just have to redo your own > work when you find out why. > > These pre-1985 keyframes were made of heavy Oak, Walnut and Maple. > They were well seasoned and held regulation well. The Renner/Kluge > keyframes are made of European species, are much lighter and are > designed for a different kind of piano altogether. > > Beginning in 1987-1988, NY began planing the keybeds mostly flat, > with areas of concavity around the maple plugs for the glides. While > some improvements have been made over the earlier keyframes, they are > wildly susceptible to weather changes, as I am sure you have discovered. > Further, their lightness of mass influences not only their ability to > hold regulation, but also their ability to transmit energy. Their > planing in the front rail area is usually limited to the last 4-6" of > distance from the ends of the keyframe, and seems to be further limited > to the keybed itself - there is little, if any, attempt to mirror the > work. The result, of course, is a keyframe which is never quite stable; > which brings me to: > > Hamburg keyframes. > > In the period immediately following W.W.II, the Hamburg pianos were, > at first, just put together from whatever could be salvaged from London > and Berlin, as well as Hamburg. There was also, for a time, some bigger > pieces coming from NY. But it was a different world. The influence of > Renner can hardly be overstated. Renner was, and is, the world's largest > producer of piano parts. They make parts to manufacturer's > specifications, to be sure; but, the manufacturers make sure their > specifications fit what Renner is set up to do. No company was/is more > in this predicament than Steinway. Has it been all bad? Definitely not, > but it has significantly influenced the course of the company. > So, what about Hamburg? > > What about it, indeed? > > Because things were in turmoil for a while, I will take an arbitrary > date of 1960 for talking about Hamburg keyframes. Yes, it was mostly > stable during the preceding 15 years, but there was variation. > Anyway, the post W.W.II Hamburg piano became a truly European > instrument. Nowhere is this more true than in the concept of the action, > and its relation to the rest of the piano. > > In Hamburg, the keybeds are generally dead flat. None of the planing > described for the NY pianos above. The action frames are what you see on > the post-1985 NY instruments, lightly built and highly susceptible to > weather changes. > > The installation is markedly different as well. All of the fitting is > done to predetermined dimensions. Keyframe, cheek block, dag and action > placement are done independently. At one point (I think it is no longer > the case), the entire action was introduced as a finished unit quite > late in the manufacturing process. The keyframe itself, while arched, is > so light that it depends on the glides for structural support. These > actions depend for their bedding on making things work. The keybed, > being flat, does not lend itself to being replaned. The keyframe, in > many of the ones I have seen, is only planed toward the ends, so that it > is a relatively sharp angle. Smoothing this angle is sometimes all that > is needed. > > END > > _______________________________________________ > caut list info: https://www.moypiano.com/resources/#archives >
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